There is no such thing as free market economy. It's a myth.
I'm quoting Andy Groove on this, there's no such thing as a free market as government, international politics, etc will always be there skewing things one way or another.This is my answer. Too broad to say $15 or $20. If you live in LA for example, 90k/year isn't a living wage.
You can try all you want for "free market", but some foreign gov may want to stop you like our gov try to protect us from competition in international market....